Patentable/Patents/US-6743728
US-6743728

Method for forming shallow trench isolation

PublishedJune 1, 2004
Assigneenot available in USPTO data we have
Inventorsnot available in USPTO data we have
Technical Abstract

A method for forming shallow trench isolation. A substrate is provided with a mask layer formed thereon. The mask layer is etched to expose a portion of the substrate, and the portion of the substrate is etched to form a trench. A liner layer is formed on the inside wall of the trench. A first dielectric layer and a sacrificial layer are sequentially deposited on the substrate such that the trench is substantially filled, wherein the first dielectric layer is formed by high density plasma chemical vapor deposition (HDPCVD). Portions of the first dielectric layer and the sacrificial layer are removed from the trench. A second dielectric layer is deposited on the substrate such that the trench is substantially filled, wherein the second dielectric layer is formed by high density plasma chemical vapor deposition (HDPCVD). A portion of the second dielectric layer is removed from the trench.

Patent Claims
27 claims

Legal claims defining the scope of protection, as filed with the USPTO.

1

1. A method for forming a shallow trench isolation, comprising: providing a substrate; forming a mask layer on the substrate; etching the mask layer to expose a portion of the substrate; etching a portion of the substrate to form a trench; forming a liner layer on the inside wall of the trench; sequentially depositing a first dielectric layer and a sacrificial layer on the substrate such that the trench is substantially filled, wherein the first dielectric layer is formed by high density plasma chemical vapor deposition (HDPCVD); removing portions of the first dielectric layer and the sacrificial layer from the trench; depositing a second dielectric layer on the substrate such that the trench is substantially filled, wherein the second dielectric layer is formed by high density plasma chemical vapor deposition (HDPCVD); and planarizing the second dielectric layer to remove a portion of the second dielectric layer from the trench.

2

2. The method as claimed in claim 1 , wherein the mask layer comprises oxide.

3

3. The method as claimed in claim 1 , wherein the mask layer comprises nitride.

4

4. The method as claimed in claim 1 , wherein the liner layer comprises oxide.

5

5. The method as claimed in claim 1 , wherein the liner layer comprises nitride.

6

6. The method as claimed in claim 1 , wherein the first dielectric layer comprises oxide.

7

7. The method as claimed in claim 1 further comprising completely removing the sacrificial layer before depositing the second dielectric layer.

8

8. The method as claimed in claim 1 , wherein the sacrificial layer is boron-doped phosphosilicate glass (BPSG).

9

9. The method as claimed in claim 8 , further comprising a flow process for planarizing and filling voids in the trench after the boron-doped phosphosilicate glass layer is deposited.

10

10. The method as claimed in claim 8 , further comprising completely removing the boron-doped phosphosilicate glass layer before depositing the second dielectric layer.

11

11. The method as claimed in claim 10 , wherein the boron-doped phosphosilicate glass layer is removed using hydride fluorine vapor (VHF).

12

12. The method as claimed in claim 1 , wherein depth of the trench is about 5500 6500 .

13

13. The method as claimed in claim 1 , wherein the second dielectric layer comprises oxide.

14

14. The method as claimed in claim 1 , wherein the second dielectric layer is planared by chemical mechanical polishing (CMP).

15

15. The methods as claimed in claim 1 , wherein the second dielectric layer is planared by etching.

16

16. The method as claimed in claim 1 further comprising spray chemical etching.

17

17. A method for forming a shallow trench isolation, comprising: providing a substrate; forming a mask layer on the substrate; etching the mask layer to expose a portion of the substrate; etching the portion of the substrate to form a trench; forming a liner layer on the inside wall of the trench; sequentially depositing a first dielectric layer and a boron-doped phosphosilicate glass layer on the substrate such that the trench is substantially filled, wherein the first dielectric layer is formed by high density plasma chemical vapor deposition (HDPCVD); depositing the boron-doped phosphosilicate glass layer to planarize and fill voids in the trench; removing portions of the first dielectric layer and the boron-doped phosphosilicate glass layer from the trench; depositing a second dielectric layer on the substrate such that the trench is substantially filled, wherein the second dielectric layer is formed by high density plasma chemical vapor deposition (HDPCVD); and planarizing the second dielectric layer to remove a portion of the second dielectric layer from the trench using chemical mechanical polishing (CMP) process.

18

18. The method as claimed in claim 17 , wherein the mask layer comprises oxide.

19

19. The method as claimed in claim 17 , wherein the mask layer comprises nitride.

20

20. The method as claimed in claim 17 , wherein the liner layer comprises oxide.

21

21. The method as claimed in claim 17 , wherein the liner layer comprises nitride.

22

22. The method as claimed in claim 17 , wherein the first dielectric layer comprises oxide.

23

23. The method as claimed in claim 17 further comprising completely removing the boron-doped phosphosilicate glass layer before depositing the second dielectric layer.

24

24. The method as claimed in claim 23 , wherein the boron-doped phosphosilicate glass layer is removed by hydride fluorine vapor.

25

25. The method as claimed in claim 17 , wherein depth of the trench is about 5500 6500 .

26

26. The method as claimed in claim 17 , wherein the second dielectric layer comprises oxide.

27

27. The method as claimed in claim 17 further comprising spray chemical etching.

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Patent Metadata

Filing Date

December 17, 2002

Publication Date

June 1, 2004

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Cite as: Patentable. “Method for forming shallow trench isolation” (US-6743728). https://patentable.app/patents/US-6743728

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